Field of the Invention
The present invention relates to a machine tool including a coolant apparatus.
Description of the Related Art
Chips generated during machining in a machine tool may accumulate by adhering to various locations around a workpiece or inside a cover put over a machining region. When chips accumulate as described above, accuracy of machining may deteriorate or the machine tool may not work normally and therefore, it is necessary to remove and discharge chips out of the machine. To remove chips accumulated inside the machine tool, a nozzle or the like that supplies a coolant to each location inside the cover put over a machining region is generally provided and the coolant is used to wash away chips.
To supply a coolant, methods such as laying a pipe for coolant supply inside an apparatus and causing an external nozzle to discharge the coolant toward a machine tool are known.
Japanese Patent Application Laid-Open No. 2005-131762 discloses a technology that provides an opening in a wall portion of a machine tool without laying a pipe inside an apparatus of the machine tool and causes the coolant to be discharged along a wall surface from an inner wall itself of the machine tool through the opening. The technology causes the coolant to pass through an opening provided in the wall portion so that the coolant is discharged along the wall surface from the inner wall itself, not from the pipe laid inside the machine. Accordingly, chips adhering and accumulating on the sidewall or at the bottom inside the machine can effectively be discharged. However, how to discharge or stop the coolant is not shown.
It is a common practice to remove chips by discharging the coolant during machining based on a command such as an M code instructed in a machining program or input from an operation panel or the like and to stop discharging the coolant when machining is finished. However, when the coolant is discharged or stopped based on a command such as an M code instructed in a machining program or input from an operation panel or the like and the discharge of the coolant is stopped when machining is finished, chips may not be completely removed when machining is finished so that chips may remain inside the machine without being completely removed.
On the other hand, when the discharge of the coolant is continued after machining is finished such as keeping discharging the coolant all the time to remove chips, power is consumed unnecessarily and there is also the possibility of the coolant splattering out of the machine when a door provided in the cover is opened. When the coolant is splattered on a floor, the floor may become more slippery and incur a danger.